Re: pthreads in libtool'd shared library...

[Ralf Wildenhues]

* Chris Bowlby wrote on Sun, Oct 31, 2004 at 02:42:51AM CET:
> 
>  Thanks for the help, but seemed to have no effect, I'm building this on a 
> FreeBSD 4.10-STABLE box, with libtool version 1.5.8.
> I  was not adding the -lc_r parameter itself, automake/configure did that 
> for me during the compile process. So far, each time I compile and try to 
> execute the command, I get the following error:
> 
> ./test
> /usr/local/test/lib/libtest.so: Undefined symbol "pthread_create"
> 
*snip*
> 
> So I can tell right off that the pthread library (in this case it should be:
> /usr/lib/libc_r.so.4
> 
> It's got to be something I'm missing in the linkage process, the current 
> Makefile.am looks like:
> 
> lib_LTLIBRARIES = libtest.la
> 
> libtest_la_SOURCES = test.cxx
> libtest_la_LDFLAGS = -module -Wsymbolic -pthread

Try adding -no-undefined.  Should fail at library link time then.

Did you check that the `-pthread' option is really passed to the
compiler?  I don't have FreeBSD available to test (and no experience
with it), but online docs suggest it to be sufficient.

More random thoughts: try putting -pthread as very last thing on the
  libtool --mode=links -o libtest.la ...
cmdline.  Try the g++ link line (which libtool generates) by hand
and try to see what's necessary to fix it.

BTW, -Wsymbolic is not mentioned in the online docs.  Is that the same
as -Bsymbolic?

> #libtest_la_LDFLAGS = -version-info 
> $(ABI_CURRENT):$(ABI_REVISION):$(ABI_AGE)

No need to remove the version-info.

Regards,
Ralf